The long-term goal of this technology development project is improve the rehabilitation of veterans suffering from lung diseases through the development of the first truly portable, biocompatible, artificial lung capable of short and long term respiratory support. Current artificil lungs have recently been used to rehabilitate lung disease patients; however, significant advances in gas exchange, biocompatibility, and portability are required to fully realize their potential. Microchannel artificial lungs promise to enable a new class of truly portable artificial lungs through feature sizes and blood channel designs that closely mimic those found in their natural counterpart. Our small-scale microchannel artificial lungs achieved the highest gas exchange efficiency of any artificial lung to date. Their lifetimes were improved through the application of custom, biocompatible surface coatings. The objectives of the current Merit Review proposal are to: 1) Increase the membrane area and rated flow of our microchannel artificial lung by a factor of 100X; 2) Further increase the biocompatibility of our microchannel artificial lung through nitric oxide release; and, 3) To perform initial gas exchange and lifetime studies in animals. These objectives are critical to advancing this promising technology towards initial acute systems for veteran pulmonary rehabilitation.